Acid rain. Innholdsfortegnelse. Side 1 / 12

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1 Acid rain Innholdsfortegnelse 1) Maps: Deposition of sulphur and nitrogen 2) Map: Areas where critical loads are exceeded Side 1 / 12

2 Acid rain Published by the Norwegian Environment Agency A great deal has been done to reduce sulphur emissions in Norway and the rest of Europe, and pollution has been substantially reduced as a result. Nevertheless, much of the southern half of Norway is still suffering from damage caused by acid rain. In 2020, Norway will still have lakes that are too acid to accommodate viable populations of trout or other fish species. Photo: Svein Nic. Norberg Liming of rivers and lakes is an important means of remedying the worst of the damage caused by acid rain. The aim is to give animals and plants a chance to re-establish themselves. In Norway, liming is most extensive in Telemark, Aust-Agder, Vest-Agder and Rogaland counties. Photo: Helge B. Pedersen Side 2 / 12

3 STATE Southern half of Norway still suffering from damage Deposition of sulfur and nitrogen can lead to acidification of water and soil. In Norway acidification, results in reduced water quality in lakes and rivers in the southern half of Norway, and especially in the southernmost counties. Over the years many fish stocks have been depleted or wiped out, and other aquatic animals and plants are also affected. Sulphur causes acidification in Norway Deposition of sulphur causes acidification in Norway, and sulphur deposition is highest in the most sensitive areas in the south. As sulphur emissions are being reduced more rapidly than nitrogen emissions, the relative importance of nitrogen as a source of pollution is increasing. Nitrogen also has other effects Nitrogen has more complex ecological effects than sulphur, because it can also act as a fertiliser and cause eutrophication. Most nitrogen is absorbed by plants or the soil, but the remainder ends up in fjords and coastal waters, where it can fuel eutrophication and excessive algal growth. Critical loads low in the southern half of Norway Critical loads are used to define the amount of pollution different ecosystems can absorb without damage to the natural environment. In Norway, freshwater ecosystems are particularly sensitive to acidification. Critical loads for freshwater are based on the effects on trout. They are particularly low in the southern half of the country, mainly because soils are thin and the bedrock consists of acidic rocks such as gneiss and granite. IMPACT Acid rain kills fish Salmon stocks lost in the southernmost counties Side 3 / 12

4 Acid rain is still a serious threat to biodiversity in rivers and lakes in Norway. In all, more than 9000 fish stocks were lost and over 5000 were severely depleted due to acidification in Similar calculations have not been performed since, but in a study from 2008, it was estimated that the area with damage to fish stocks in Norway was reduced from around km2 in 1990 to km2 in 2006, a reduction of about 38 percent. Little or no damage to Norwegian forests In the 1980s, acid rain resulted in widespread damage to forests in the border areas between Poland and the former East Germany and Czechoslovakia. There was serious concern about similar damage in Norway, and in 1984 the Norwegian Monitoring Programme for Forest Damage was started. On the whole, Norwegian forests appear to have tolerated sulphur and nitrogen deposition without serious effects. They showed a decrease in vitality (measured as crown density) during the 1990s, but since then conditions have improved. In the last few years, the health of Norwegian forests has remained stable. Major economic consequences In addition to its effects on ecosystems, acid rain has serious consequences for society as a whole. One example is that loss of fishing opportunities can lead to economic losses for businesses in the affected areas. About million NOK has been spent annually on liming of rivers and lakes in recent years. Acidification may also damage buildings, sculptures, rock art and other parts of our cultural heritage. DRIVING FORCES Trends determined by energy use Acid rain is mainly caused by combustion of fossil fuels. More than 90 per cent of the sulphur and 80 per cent of the nitrogen deposited in Norway originates in other European countries. The UK, Germany, Poland and the North Sea are among the most important sources. This means that the amount of acid rain falling on Norway is to a large extent determined by developments elsewhere in Europe. The European emissions have been greatly reduced over the last years. This is largely due to technical improvements in industrial processes, and a transition from coal to fuels with less sulphur. There has not been a corresponding reduction in the emissions of nitrogen, because these emissions are highly influenced by the use of transport. PRESSURE Industry and transport the main sources Power plants, industrial processes (especially metal production) and transport are the main sources of acidifying emissions. Sulphur and nitrogen deposition in Norway declining Inputs of sulphur and nitrogen to Norway have declined as emissions in Europe have been reduced. However, there has been a much smaller overall reduction for nitrogen (sum of oxidised and reduced nitrogen) than for sulphur. There are several reasons for this: it took much longer before people began to focus on the harmful effects of nitrogen it took longer before international agreements on the reduction of nitrogen emissions were concluded the mix of sources is different for nitrogen, and this has made it more difficult to find effective ways of reducing emissions. Side 4 / 12

5 Estimates of inputs of sulphur and nitrogen to Norway tonnes Nitrogen Sulphur Source: European Monitoring and Evaluation Programme (EMEP) Licence: NLOD Total deposition of sulphur in Norway was reduced from about tonnes in 1980 to tonnes in 2012, a reduction of more than 85 per cent. Total deposition of nitrogen in Norway was about tonnes in 1980, and increased to in From 1990 to 2012 deposition was almost halved, from tonnes to tonnes. Norwegian sulphur and nitrogen emissions declining In Norway, the main sources of sulphur dioxide emissions are metal production, stationary combustion and other industrial processes. Norwegian emissions have been greatly reduced, from about tonnes a year in the 1970s to about tonnes in The main sources of nitrogen emissions in Norway are the oil and gas industry, coastal shipping, fishing vessels and road traffic. In 2014, emissions were about tonnes. In addition, there was a total emission of tonnes of the nitrogen compound ammonia. Side 5 / 12

6 Norwegian emissions of acidifying gasses tonn Nitrogen Ammonia Sulphur Source: Statistisk sentralbyrå (SSB) Lisens: Norsk Lisens for Offentlige Data (NLOD) RESPONSE International agreements are vital Acid rain does not respect national borders, and is a problem for most European countries. The answer has been to join forces to reduce overall European emissions of sulphur and nitrogen. Binding international agreements Most European countries have undertaken to reduce their emissions of acidifying substances through the Convention on Long-range Transboundary Air Pollution (LRTAP). Several binding protocols have been adopted under the convention, including the Gothenburg Protocol, which entered into force in Initially emissions ceilings were set for 2010, but the protocol was renegotiated in 2012 and new emissions ceilings (to be met in 2020) have been set. Norway met the 2010 emission ceiling for sulphur dioxide in 2006, while emission ceilings for ammonia and nitrogen oxides were not met. The emissions of ammonia were about 4000 tonnes above the target of tonnes in For nitrogen oxides the emission ceiling was tonnes in 2010, while the Norwegian emissions were about tonnes. In the revised Gothenburg Protocol, Norway has undertaken to reduce emissions of sulphur dioxide, ammonia and nitrogen, by respectively 10, 8 and 23 per cent relative to emissions in For Norway, the new requirements represent only minor changes. For sulphur dioxide, the target was reached already in For nitrogen oxides he target was reached in Emissions of ammonia must be reduced from tonnes in 2013 to tonnes in 2020, Liming reduces damage Liming of rivers and lakes is an important means of remedying the worst of the damage caused by acid rain. The aim is to give animals and plants a chance to re-establish themselves. Each year tonnes are applied in Norwegian rivers and lakes. The liming programme is most extensive in Telemark, Aust-Agder, Vest-Agder and Rogaland counties. Side 6 / 12

7 1. Maps: Deposition of sulphur and nitrogen Published by the Norwegian Environment Agency In 1980 acidification was one of the major pollution problems in Norway. The main cause was emissions of sulphur and nitrogen in countries further south in Europe. There were small changes in the deposits from 1980 to the early 1990's. From the mid-1990s, conditions in Norway began to improve, as emissions in Europe declined. Estimates from 2012 show that emissions have continued to decline in recent years, but not as much as earlier. The maps below show the reductions in deposition of sulphur and nitrogen in Norway from 1978 to New figures will be published in Side 7 / 12

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10 2. Map: Areas where critical loads are exceeded Published by the Norwegian Environment Agency Critical loads are used to define the amount of pollution different ecosystems can absorb without damage to the natural environment. In Norway, the area where critical loads are exceeded has decreased since In 1980 critical loads were exceeded in 30 percent of the total area. In 2005, the area was reduced to 10 percent. Similar figures for 2012 were 8 per cent. The map below shows the reductions in areas where critical loads were exceeded in Norway from 1978 to New figures will be published in Side 10 / 12

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